Drill stem protector



Aug. 19, 1941. v. PARKIN DRILL STEM PROTECTOR 7 Filed June 22, 1938 In m n for Viv/0r 3 Par/Vziz Patented Aug. 19, 1941 UNITED STATES PATENT OFFICE 2,252,978 DRILL STEM PROTECTOR Victor Parkin, Los Angeles, Calif. Application June 22, 1938, Serial No. 215,157

(01. 3084) This invention relates to protectors for drill 4 Claims.

stems of the character employed in oil well drilling operations "as a means for preventing the stem from coming into direct contact with the wall of the well bore during operation of the drill; the invention more particularly pertaining to the type of drill stem protector embodying a cushion member formed of rubber or similar resilient material, together with means for securing said cushion member to a drill stem. 1

The primary object of the present invention is to produce an improved construction in protectors of the above character whereby the cushion member may be easily and quickly applied to the stem without liability of accidental disengagement of the protector either during or after its application, which has been known to occur with protectors of the character now generally in use, and which accidental disengagement may result in injury to workmen or to the objectionable depositing of the protector parts in the well bore.

Another object is to provide a construction whereby the protector may be affixed to the stem by a plurality of independently operated clamp-- ing bands so as to require a minimum of effort in operating the clamping mechanism in applying the protector to the stem.

Another object is to provide a protector with a clamping means which embodies a locking element such as to insure against accidental disengagement of the clamp.

A further object is to provide a protector clamp which is so formed as to enable its operation by 35 a tool whereby application of the protector to a drill. stem and its removal therefrom is facilitated.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the invention is carried into efiect as illustrated by way of example in the accompanying drawing, in which:

Fig. l is a view in side elevation of the protector showing it as applied;

Fig. 2 is a View in horizontal section taken on the line 2-2 of Fig. 1;

Fig. 3 is a view in perspective of a clamping band showing it as detached; Fig. 4 is a perspective View of an interlocking pin for fastening the ends of-the clamping band together;

Fig. 5 is a plan view depicting the manner of in effecting fastening of the protector cushions on a drill stem.

Referring to the drawing more specifically A indicates a fragmentary portion of a tubular drill stem and B designates generally the protector embodying the invention which is designed to be mounted on thestem A to encompass the latter at any convenient point throughout the length thereof.

As here shown the protector embodies a longitudinally divided cylindrical resilient shoe 6 having its inner periphery conformable to the outer periphery of the stem A to which the shoe is applied to substantially encompass the stem; the. shoe being so dimensioned that when applied to the stem its contiguous longitudinal margins will be slightly spaced apart to form a gap a therebetween. Formed on theouter face of the shoe 6 integral therewith is a series of circumferentially extending radially projecting bumpers l; a series of four of the bumpers being provided adjacent each end of the shoe with the bumpers at one end slightly spaced from the bumpers at the other end to provide a circumferential channel 0 intermediate the ends of the shoe and between the bumpers on each end portion of the shoe. The adjacent bumpers of each end series are spaced apart and the adjacent ends of the bumpers contiguous the longitudinal margins of the shoe are spaced apart to provide a vertical channel D therebetween. The bumpers have their outer faces formed on longitudinal curvatures which when the shoe is assembled on the drill stem the outer faces of the bumpers will collectively coincide with a circle .concentric with the drill stem in outwardly Spaced relation thereto.

The ends of the shoe 6 are formed with outwardly projecting flanges 8 which are spaced slightly from adjacent bumpers l and provide circumferential channels E proximate the ends of the shoe.

In carrying out the invention a series of independent clamping bands F are provided to encompass the shoe 6; oneof the bands being positioned in the channel C intermediate the ends of the shoe, and a band being disposed in each of the channels E adjacent the ends of the shoe. The circumferential zones between the 0 applied bands are occupied by the bumpers l which extend across the width of each of such zones.

Each of the bands F is split and is formed at one end thereof with a yoke 9 the ends of the applying the. clamping band by means of a tool side members of which are formed with elongated loops l and II the openings of which are substantially rectangular in outline and are disposed in opposed alignment with each other. The other end of the band is formed with a loop l2 having an elongated opening of substantially rectangular entrant end portion l3 and an opposed headed,

end portion 14. A notch I5 is formedalong at least one longitudinal margin of the pin which notch terminates at its ends in, abruptshoulders It and is of a length slightly exceeding the height 2l--22 and the band in' place, which is accomplished by engaging the link 3| with one of the notches 32 and then manipulating the lever 29 to its locking position.

A pin G is then inserted through the registering loops l0, l2 and II and positioned to bring the notch 15 thereon opposite the outer end wall of the loop 12, whereupon the tool is released to allow the band F to expand and thereby cause the loop I2 to efiect engagement with the notch 15 and whereby the pin G will be securely locked in place against accidental disengagement.

In like manner the other clamping bands are put in place so as to securely bind the protector "shoe onto the stem in such fashion as not to be liable to accidental disengagement. However, by

of the loop [2 so that the outer end of the loop [2 may be engaged in the notch.

Provision of the plurality of independent clamping bands F enables the employment of a simple hand operated tool in effecting application of the protector to the drill stem and also its removal therefrom, and with greater facility than in other types of protectors now generally in" use and particularly those requiring the employment of expanders. Such tool and the mode of application of the protector is shown in Fig. 5; the tool embodying a pair of lever-arms II and L8 connected by pivots I9 to the ends of a link Zflpand on which arms is mounted a pair'of jaws 2| and 22 which are connected to the arms by pivots 23.

The jaws 2| and 22 are formed with arcuate inner faces I) of a curvature substantially conforming to that of the outer perimeter of a band F when the latter is in its applied position. The base end portions of the jaws 2i and 22 are connected. by. pivot pins 24 to lugs 25 and 25 afiixed to the ends of a plate spring 21; which spring is adapted to be bent to conform to the band' F and is arranged that when; so bent it willabut-ashoulder 28 on the link 28. The free endsfof the. jaws 2'! and 22 are offset relative to each other so that they may overlap each other during application of the band F.

Mounted onthe outer end of the arm ll is a crank armf29'which is connected to the arm ll by apivot 3B and, which crank arm carries a looplink 3| adapted tobe engaged at its outer end withone or aseries of stepped notches 32 formed on the outer endof the arm I8.

employing the applicator tool, as shown in Fig. 5, the bands F may be contracted such as to free theloop I2 from the notch [5 of a pin and thereby permit' withdrawalof thepin when desired tofremove the protector from the stem.

It is manifest that when the stem is equipped with I the protectors at suitable intervals throughout its length, the bumpers i will act when the stem-is in a Well bore to prevent the stem from coming into *directcontact with the walls of the well bore. By providing the protector with the bumpers I spaced apart circumferentially of the protector ample space is pro-. vided for the flow of circulating mud along the length of the stem and well bore.

Owing to the fact that each of the clamping bands is independent from the others, and can be independently'applied, the power exerted by the workman in clamping the shoe in place is applied to a small portion of the length. of the shoe at each clamping operation, hence a more forcible clamping of the bands is possible than In the, application and operation of the inyen-tion, attachment of the protector to the drill stem is effected by spreading the shoe along its divided portion and positioning it astriole the stem. to encompass the latter. The bumpers l and channels C and E of the shoe will'then be disposed in circumferential alignment around the stem. One of the clamping bands'F is then positioned astride the assembled shoe in one of the channel's E or the channel C; the band being formed of spring metal and being spread at its endsto such extent as to permit its being placed around the protector shoe. The jaws Zl and 22 of the applicator tool are then engaged'with the band and the arms I1 and Hiof the tool are manipulated to effect contraction of the clamping'band. to such extentthat the loop it! will be positioned between and in register with the loops [0 and It, during which operation the resilient shoe 6 W-ill be tightly compressed against the stem, The arms If! and 18 may then be fastened against spreading to hold the jaws could be obtained if more than one longitudinal section of the clamping means were applied at the same time.

While I have described the protector as utilized in connection with a drill stem, it may also be employed on sucker rods of a pump, and in any other construction where a bumper of this character would be serviceable, and while I have shown and described a specific embodiment of the invention it will be understood as embrac-. ing such changes in construction and arrangeinent of the parts as come within the meaning and scope of the appended claims.

I claim:

1. A drill stem protector comprising a longitudinally divided cylindrical resilient shoe formed with a plurality of spaced circumferentially'extending outwardly projecting bumpers adjacent each end thereof, said shoe having its inner face formed to seat on and conform to the outer periphery of a drill stem, a. plurality of independent split clamping bands encirclingv said shoe adjacent said. bumpers, loops on the ends of said bands, and pins insertable in said loops connecting the ends of the bands together; each of said pins being formed with a notch on a margin thereof to receive at least one of said loops in interlocking engagement therewith.

2. In a protector for drill stems and the like, a resilient shoe conformable to the circumferential surface of the stem, bumpers on said shoe, a spring clamping band encircling the shoehaving loops on its end portions, a pin demountably inserted through said loops; said band. and the portions of said shoe encircled thereby being compressed whereby a longitudinal pull is imparted to said band tending to spread the ends thereof; and means whereby the pull on the ends of said band will effect interlocking engagement between said band and said pin, said means including a notch in a side edge of said pin arranged to be engaged by a closed end of at least one of the loops on an end portion of said band.

3. In a stern protector, a shoe formed for positioning on a stem, a split clamping band encircling the shoe, a yoke on one end of said band having loops forming the ends thereof, a loop on the other end of said band adapted to be positioned between said yoke loops, and a pin insertable through said loops; said pin being formed With a notch arranged to be engaged by the closed end of said last named loop to hold the pin against removal from said loops, said notch being in a side edge of said pin and being of a sufiicient length to receive the width of said loop.

4. In a structure of the kind described, a body of rubber-like material, said body comprising a cylindrical part which is longitudinally split; an external circumferential band around each end portion thereof, spaced rows of outwardly projeeting circumferentially extending bumpers spaced away from said heads, a clamping band occupying each of the circumferentially extending spaces thus provided, and independent fastening means cooperating with the end portions of each of said bands to maintain it in a gripping position in relation to the cylindrical portion of said body.

VICTOR PARKIN. 

